Pull-off mechanism for stitching-machines.



H. THEISEN & G. S. KELLER.

PULL-OPP MECHANISM FOR STI'I'OHING MACHINES.

APPLICATION FILED MAY 13, 1909.

Patented Jan. 24, 1911.

m NORRIS FEfE UNITED STATES Parana OFFICE.

BRUNO H. THEISEN AND GEORGE S. KELLER, OF MINNEAPOLIS, MINNESOTA.

PULL-OFF MECHANISM FOR STITCHING-MACHINES.

To all whom it may concern:

Be it known that we, BRUNO I'I. TI-IEISEN and GEORGE S. KELLER, both ofMinneapolis, Hennepin county, Minnesota, have invented certain new anduseful Improvements in Pull-Off Mechanisms for Stitching-Machines, ofwhich the following is a specification.

The object of our invention is to provide means for regulating thetension of a thread on a stitching machine, to the end that the amountof thread used in each stitch can be controlled.

The invention. consists generally in various constructions andcombinations, all as hereinafter described and particularly pointed outin the claims.

In the accompanying drawings, forming part of this specification, Figure1 is a sectional view, illustrating the application of our invention toa stitching machine, Fig. 2 is a detail view, showing the mechanism,which controls the feed of the thread, Fig. 3 is a View, taken on aline, substantially at right angles to the sight line of Fig. 2, Fig. 4is a detail view, illustrating the manner of running the thread from thereel to the work plate and putting the required tension thereon.

In the drawing, 2 re resents the frame of the machine, 3 a sha carryinga cam 4 7 adapted to engage an arm 5, mounted on a bracket 6, whichprojects from an oscillatin shaft 7. An arm 8 is carried by said shaftand is adapted to engage and oscillate a j aw 9, by the movement ofwhich the work is fed through the machine.

10 represents the needle jaw and 11 is an arm, carrying a shuttle 12.These parts however, form the subject matter of separate applicationsfor Letters Patent, Serial No. 495,742, filed May 13, 1909, and SerialNo. 365,541, filed March 30, 1907.

Referring to Fig. 4, 13 represents a reel on which the thread is woundand from which the thread passes to the holes 14 and 15, provided in anarm 16, which projects from the frame 2. A lever 17 is pivoted at 18 onthe frame, and carries a thread-engaging device 19, which as hereinshown, is in the shape of a laterally projecting pin. The thread passesfrom the hole 15 in thearm 16 over the thread-engaging device or pin 19,through the hole 20 or thread guide; thence around and over the pin 19,and through the hole or thread guide 21 in the arm 16. A

Specification of Letters Patent.

Application filed May 13, 1909.

Patented Jan. 24, 1911.

Serial No. 495,740.

lever 22, as herein shown, is pivoted at 18 and at its free endcooperates with a cam 25. A spring 24 engages the lever 22 and normallyholds the same in operative engagement with the cam 25. The lever 22 isprovided with a projecting stud which is dis posed opposite a similarprojecting stud on the lever 17, and a compression spring 23 engagingsaid studs, operates to separate the levers 22 and 17 The tension ofsaid spring 23 is so proportioned that the normal tension on the thread,due to the movements of the needle and the feed of the material, willdraw the thread-engaging device or pin 19 against the arm 16. As the cam25 rotates, the lever 22 will be oscillated, and the sprin 23compressed, which will cause the lever 17 to move outward, carrying thepin 19, over which the thread is laid outward away from the threadeyelets or holes 15, 20 and 21, in the arm 16, and thus pull up theneedle thread. The outward movement of the arm 17 is limited by a stopscrew 25, which has the usual lock nut. By adjusting the stop screw 25,the amount of take-up action on the needle thread is regulated. When itis desired to have the thread taut in the material, and a very tightstitch made, then the stop screw 25 is moved outward, so as to allow alonger throw of thelever 17. By moving the stop screw in, the .throw ofthe lever 17 will be shortened, and less thread taken up, thus making alooser stitch. It is obvious that the stop screw 25 may also be adjustedfor varying lengths of feed, so as to make a stitch of any desiredcharacter. After leaving the pin 19, the thread is carried through ahole 26 in a pin 27 and from thence through tension devices 28, 29 and30 to an oscillating hook tension 31 and to a wheel 32 carried by thearm 8, and from thence to a hole in the work plate 33. The thread iswaxed and very strong and the series of tensions are for the purpose ofkeeping it drawn taut and insuring a close, tight stitch in thematerial. A wax pot 27 is carried by the lower end of the pin 27.

We claim as our invention 1. In a stitching machine, the combination ofthread guides, an oscillating arm, a thread-engaging device carried bysaid arm, means for moving said arm to carry said thread-engaging deviceaway from said thread guides to take up the thread, said means includingan oscillating member, means for oscillating the same, a yielding partconnecting said oscillating member'and said arm, whereby saidthread-engaging device is yieldingly moved away from said thread guide,and an adjustable stop for engaging said arm for limiting the movementthereof away from said thread guide to vary the amount of thread takenup.

2. In a stitching machine, the combination of an oscillating member,means for operating the same, an oscillating arm supported independentlyof said member, a thread-engaging device carried by said arm, meansincluding a yielding part for connecting said arm and said member,whereby said arm is moved by said member, and an adjustable stop jorlimiting the movement of said oscillating arm.

3. In a stitching machine, the combination with a frame, a lever pivotedthereon, a thread engaging pin carried by said lever, a second leverpivoted to said frame, a cam for oscillating said second lever, a springholding said second lever in engagement with said cam and a compressionspring interposed between said levers whereby movement of said secondnamed lever is imparted to said first named lever.

4. In a stitching machine, the combination with a frame, a lever pivotedthereon, a thread engaging pin carried by saidlever, a second levermounted on the same pivotal support as said first named lever, a cam, aspring for holding said second lever in engagement with said cam, acompression spring interposed between said levers whereby the movementsof the second lever are yieldingly imparted to the first named lever,and an adjustable stop located in the path of movement of said firstnamed lever for limiting the movements thereof.

In witness whereof, we have hereunto set our hands this Qltll day ofApril 1909.

BRUNO H. THEISEN. GEORGE S. KELLER.

lVitnesses J nssm M. SULLIVAN, J. A. BYINGTON.

